Disruption of alternative NAD(P)H dehydrogenases leads to decreased mitochondrial ROS in Neurospora crassa

• Type: Article in International Scientific Journal
• Date: 2012

Authors

carneiro, p (Author) Other; duarte, m (Author) Other; videira, a (Author) ICBAS

Journal

Title: Free Radical Biology and Medicine

Vol. 52

Pages: 402-409

ISSN: 0891-5849

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 3 Citations

Scopus - 4 Citations

Other information

Authenticus ID: P-002-DX9

DOI: 10.1016/j.freeradbiomed.2011.10.492

Abstract (EN): Mitochondria are a main providers of high levels of energy, but also a major source of reactive oxygen species (ROS) during normal oxidative metabolism. The involvement of Neurospora crassa alternative NAD(P)H dehydrogenases in mitochondrial ROS production was evaluated. The growth responses of a series of respiratory mutants to several stress conditions revealed that disrupting alternative dehydrogenases leads to an increased tolerance to the redox cycler paraquat, with a mutant devoid of the external NDE1 and NDE2 enzymes being significantly more resistant. The nde1nde2 mutant mitochondria show a significant decrease in ROS generation in the presence and absence of paraquat, regardless of the respiratory substrate used, and an intrinsic increase in catalase activity. Analysis of ROS production by a complex I mutant (nuo51) indicates that, as in other organisms, paraquat-derived ROS in Neurospora mitochondria occur mainly at the level of complex I. We propose that disruption of the external NAD(P)H dehydrogenases NDE1 and NDE2 leads to a synergistic effect diminishing ROS generation by the mitochondrial respiratory chain. This, in addition to a robust increase in scavenging capacity, provides the mutant strain with an improved ability to withstand paraquat treatment. (C) 2011 Elsevier Inc. All rights reserved.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8